C and JNI

C/getenv.c

@@ -0,0 +1,41 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#ifndef TRUE
+#define TRUE 1
+#define FALSE 0
+#endif
+
+int nativeDebugEnabled() {
+  char * nativeDebug = "NATIVEDEBUG";
+  int debug = FALSE;
+  if (getenv(nativeDebug)) {
+    if (strcmp("true", getenv(nativeDebug)) == 0) {
+      debug = TRUE;
+    }
+  }
+  return debug;
+}
+
+int main () {
+  char * user  = "USER";
+  char * shell = "SHELL";
+
+  fprintf(stdout, "User:%s, Shell:%s\n", getenv(user), getenv(shell));
+
+  char * olivDebug = "OLIVDEBUG";
+  int debug = FALSE;
+  if (getenv(olivDebug)) {
+    if (strcmp("true", getenv(olivDebug)) == 0) {
+      debug = TRUE;
+    }
+  }
+  fprintf(stdout, "%s is %sset.\n", olivDebug, (debug ? "" : "not "));
+
+  fprintf(stdout, "NATIVEDEBUG is %sset\n", (nativeDebugEnabled() ? "" : "not "));
+
+  return 0;
+}

I2C.SPI/src/lcd/oled/SSD1306.java

@@ -59,7 +59,7 @@ public class SSD1306 {
 	private int width = 128,
 							height = 32;
 	private int clockHertz = 8_000_000; // 8 MHz
-	private int vccstate = 0;
+	private int vccstate = 0; // or SSD1306_EXTERNALVCC
 	private int pages = 0;
 	private int[] buffer = null;
 
@@ -351,7 +351,7 @@ private void initialize() { // SPI, 128x32
 		else
 			this.command(0x14);
 		this.command(SSD1306_MEMORYMODE);          // 0x20
-		this.command(0x00);                        // 0x0 act like ks0108
+		this.command(0x00);                     // 0x0 act like ks0108
 		this.command(SSD1306_SEGREMAP | 0x1);
 		this.command(SSD1306_COMSCANDEC);
 		this.command(SSD1306_SETCOMPINS);          // 0xDA

JNISample/C/HelloWorld.c

@@ -24,7 +24,7 @@ JNIEXPORT void JNICALL Java_jnisample_HelloWorld_print (JNIEnv * env, jobject ob
 JNIEXPORT jint JNICALL Java_jnisample_HelloWorld_manageObject (JNIEnv * env, jobject obj1, jobject obj2) {
   printf("C receiving Java Object\n");
   jclass objClass = (*env)->GetObjectClass(env, obj2);
-  jfieldID fidInt    = (*env)->GetFieldID(env, objClass, "someNumber", "I");
+  jfieldID fidInt = (*env)->GetFieldID(env, objClass, "someNumber", "I");
   jint iVal = (*env)->GetIntField(env, obj2, fidInt);
   printf("- Value: %d\n", iVal);